If:
Then:
Example:
| عَجَاوِزُ | → | عَجَائِزُ |
| شَرَايِفُ | → | شَرَائِفُ |
| رَسَاالُ | → | رَسَائِلُ |
Note: changing a root letter that is a ḥarf ʿillah to a hamzah is rare.
Example:
| مَصَايِبُ | → | مَصَائِبُ |
When wāw or yāʾ falls at the end of a word after an alif zāʾidah, it is converted to a hamzah.
On the scale of fuʿlā with a wāw lām, the wāw turns to yāʾ; on faʿlā with a yāʾ lām, the yāʾ turns to wāw.
Morphological rule: a ي in the lām position after a ḍammah converts to a و.
When wāw falls on the fourth letter or later and is not preceded by a ḍammah or wāw sākin, it is converted to yāʾ.